Structure of seven organic acid–base adducts formed between acids, 2-aminophenol, and 2-amino-4-chlorophenol

Studies concentrating on hydrogen bonding between the base of 2-aminophenol, 2-amino-4-chlorophenol, and acidic compounds have led to an increased understanding of the role 2-aminophenol, and 2-amino-4-chlorophenol have in binding with acidic compounds. Here anhydrous and hydrated multicomponent crystals of 2-aminophenol, and 2-amino-4-chlorophenol have been prepared with 2,4,6-trinitrophenol, p-nitrobenzoic acid, 3,5-dinitrobenzoic acid, 5-nitrosalicylic acid, 3,5-dinitrosalicylic acid, and fumaric acid. The crystals and complexes of the seven organic acid–base adducts were characterized by X-ray diffraction analysis, IR, mp, and elemental analysis. The seven crystalline forms reported are organic salts except 2. All of the adducts were formed in solution and obtained by the slow evaporation technique. All supramolecular architectures involve extensive NH⋯O, OH⋯O, and CH⋯O hydrogen bonds as well as other nonbonding interactions. The role of weak and strong hydrogen bonding in the crystal packing is ascertained.